Solar PV System Sizing Calculator

Calculate solar panel array size, inverter rating, and annual energy production for grid-tied PV systems.

Average daily electricity use.
kWh/day
Average daily peak sun hours for your location. US avg: 4-6.
h/day
Inverter, wiring, soiling, degradation. Typical: 14-20%.
%
Watt rating per panel. Modern: 350-450W.
W
Voltage at max power per panel.
V

Results

Required Array Size-kW
Number of Panels-
Annual Energy Production-kWh
Min Inverter Size-kW
Approx Roof Area-m²
References: NEC Article 690; IEC 62548; NREL PVWatts